Wobble plate structure



' NOV; 24, .J HOLMES 2,302,995

WOBBLE PLATE STRUCTURE Filed June 12, 1941 3 Sheets-Sheet l 'HZQ 10 Nov. 24, 1942. w y F. ,1. HOLMES 599 woasm: PLATE swnucma Filed June .12. 1941 s Sheets-She 2 Q8 E IrederickJHobnes Nov. 24, 1942. F. J. HOLMES .3 3

' WOBBLE PLATE STRUCTURE lfiled June 12, 1941 s Shuts-sheet s y 3 -Iisderilk JEobizeS,

Patented Nov. 24, 1942 WOBBLE PLATE STRUCTURE Frederick .1. Holmes, Detroit, Mich.

Original application February 15, 1939, Serial No. 256,503. Divided and this application June 12, 1941, Serial No. 397,799

4 Claims.

This invention relates to internal combustion engines, and has particular reference to improvements in internal combustion engines of the type comprising two annular series of cylinders disposed in opposed relationship to each other about a power shaft having a wobble plate structure with which the connecting rods of the engine pistons are operatively connected whereby said shaft is rotatably driven in response to reciprocation of said pistons,

Generally speaking, the object of the present invention is to provide a wobble plate structure and control means therefor, combined with connections between the same and the connecting rods of the engine, whereby the connecting rods are advantageously relieved of lateral thrust.

Another object of the invention is to provide a simple, practical, strong and durable wobble plate structure which operates with very low frictional losses.

With the foregoing and other objects in view, which will become more fully apparent as the nature of the invention is better understood, the,

same consists in the novel features of construction, combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawings and defined in the appended claims.

In th accompanying drawings, wherein like characters of reference denote, corresponding parts in the different views Figure l is a central, longitudinal section through a portion of an internal combustion engine of the opposed cylinder type equipped with a wobble plate structure constructed in accordtion.

Figure 2 is a cross section on the line- 22 of Fig. 1; and

Figure 3 is a section on the line 33 of Fig. 2.

This application is a division of my prior application, Serial No. 256,503, filed February 15, 1939.

Referring to the drawings in detail, I0, I41 designate portions of a pair of cylinder blocks and il designates a casing member rigidly connecting said cylinder blocks together in end to end, spaced apart relationship.

In each cylinder block Ill is an annular series of cylinders 12, while reciprocable in each cylinder of each block is a piston l3.

The number of cylinders in the blocks 10' is arbitrary, but both blocks have the same number of cylinders and the cylinders of the respective blocks are axially alined with eachother. Moreance with a practical embodiment of the invenover, said cylinders are equi-di'stantly spaced apart angularly and are disposed concentrically about a power shaft M which is rotatably mounted in bearings l carried by said cylinder blocks, while connecting together related or alined pistons of the respective cylinder blocks are rods I6.

Carried by the power shaft H! at a point midway between the inner ends of the cylinder blocks I0 is a wobble plate structure which comprises in the present instance a hub II on the power shaft M anda two-part ring element, designated generally as l8, which is mounted on said hub for free rotation relative thereto through the instrumentality of an anti-friction bearing designated generally as l9.

The hub I! may be formed either as an integral part of the power shaft l4 or as an element separate from said shaft and fixed thereto in any suitable manner. In either case, said hub is disposed at a suitable inclination to the power shaft l4 with its axis intersecting the axis of said shaft at a point approximately midway be tween the inner ends of the cylinder blocks I0.

At one end of the hub I1 is an annular flange 2|], while fitted upon said hub and engaged at one side edge thereof against said flange is an inner race member 2| of the anti-friction bearing I9 which inner race member is clamped against said flange by a nut 22 threaded upon the other end of said hub.

The ring element [8 is divided in a plane preferably midway between its sides and at right angles to the axis thereof into two mating halfsections designated as 23, 23 which may be reversed duplicates of one another and which, in accordance with the invention, may be fastened together in any suitable manner as, for example,

through the instrumentality of bolts 24.

Fastened between flanges 25 which extend inwardly from the two half-sections 23, 23 of the ring element 18' is the outer race element 25 of the anti-friction bearing I9, while interposed between said outer race element 26 and the aforesaid inner race element 2| are balls or other suitable rolling bodies 21 whereby said ring element In the ring element I8 is a series of sockets 30 which correspond in number to the number of connecting rods and which open through the periphery of said ring element and are equidistantly spaced apart therearound. These sockets are of spherical form and each of them snugly accommodates a related roller 29 which is universally movable therein.

Half-portions of the sockets 30 are formed in the respective half-sections 23, 23 of the ring element I8 and these half-portions are registered to form the complete sockets when the two halfsections of said ring element are bolted together. By forming the ring element I8 of two halfsections, accurate forming of the sockets 30in said ring element and disposing of the rollers'29 in said sockets obviously is greatly facilitated.

Means separate from the connecting rods I6 is provided to hold the ring element. I8 against rotation whereby reciprocation of said rods to web:

ble the wobble plate structure and thereby rotate the shaft I4 does not result in undesirable lateral thrust upon said rods. In the present instance this means comprises, generally speaking, a pair of fixed guides 3|, 3| located at opposite sides, respectively, of the ring element I8 and a pair of arms 32, 32 extending from opposite sides, respectively, of said ring element and cooperating at their outer ends with said guides.

The arms 32 may be carried completely by either section 23 of the ring element I8 either as integral parts thereof or as parts separate therefrom and fastened thereto in any suitable manner, or they may comprise mating half-portions carried by the sections 23, 23 either as integral parts thereof or as parts separate therefrom and fastened thereto in any suitable manner. In the present instance they are composed of mating half-portions integral with the respective ring sections 23, 23 and at their outer ends are provided with cylindrical or other suitable formations 33 on which are mounted suitable bearing blocks 34 which cooperate with the guides 3|.

The guides 3I may be integral parts of the casing member II or parts separate from said casing member and suitably fixed thereto or fixed in any other suitable manner at opposite sides of the ring element 26. In any event, said guides 3i extend longitudinally of the engine and preferably are curved on radii struck from the point of intersection of the axis of the hub I! with the axis of the shaft I4, and the axes of the formations 33 are alined with each other and with the said point of intersection of the axis of the hub I! with the axis of the shaft I4. Accordingly, the ring element I8 is free to swing in a single plane including the axis of the shaft I4 and to rock about the alined axes of the arms 32, but is held against rotation about the hub II. Therefore, the connecting rods I6 are relieved of lateral forces such as might be imposed thereon in the absence of means for holding the ring element I8 against rotation about the hub IT.

The inclination of the wobble plate structure relative to the shaft I4 determines, of course, the stroke of the pistons I3, and in this connection it will be understood, of course, that the spaced apart relationship of the cylinder blocks III, I II and the lengths of the cylinders I2 are such in relation to the inclination of the wobble plate structure that the pistons partake of properlength strokes in the cylinders I2.

The guides 3| are illustrated in the present instance as being of channel form in cross section and as accommodating the bearing blocks 34. Said guides may, however, be of any other suitable form and the ends of the arms 32 may be adapted in any suitable manner to cooperate with said guides.

Any suitable means may be provided to control supply of fuel to the cylinders I 2, ignition of charges compressed by the pistons I3 and exhaust of products of combustion from the cylinders, such means forming no part of the present invention and therefore not being illustrated. However, the firing order of the cylinders of both blocks preferably is successive either clockwise or counter-clockwise and alternate and substantially diametrically opposite as regards the cylinders of the respective blocks. In other words, first one cylinder of one of the blocks fires, then the substantially diametrically opposite cylinder of the other block fires and so on successively around the respective series of cylinders. Delivery of power to the wobble plate structure thus is substantially balanced and substantially continuous, assuming that the blocks I0, I0 have a substantial number of cylinders.

Due to the inclination of the hub I1 and the ring element I8 relative to the shaft I4 and to the combined oscillatory and rocking motion partaken of by said hub and ring element, every point on the'ring element I8, except those alined with the axes of the arms 32, moves in an elliptical path as the shaft I4 is rotated, these paths being of greatest length and width with respect to points on the periphery of the ring element I8 in a plane including the axis of the shaft I4 and at right angles to the axes of the arms 32 and being of gradually decreasing length and width with respect to points on the periphery of said ring element progressively nearer to the axes of the arms 32. Due, however, to the connecting rods I6 being provided with the arms 28, said arms swing slightly transversely of the engine and the rods I6 oscillate in response to their swinging to compensate for the elliptical paths of travel of the rollers 29 as the wobble plate structure wobbles during operation of the engine. Any objectionable lateral thrust on the connect ing rods I6 thus is avoided.

Without further description it is thought that the features and advantages of the invention will be readily apparent to those skilled in the art, and it will of course be understood that changes in the form, proportion and minor details of construction may be resorted to, without departing from the spirit of the invention and scope of the appended claims.

I claim:

1. A structure of the character described comprising a rotatable shaft, a hub fixed with respect to said shaft for rotation therewith, the axis of said hub being inclined relative to the axis of said shaft, a ring element mounted on said hub coaxially therewith and with respect to which said hub is rotatable, an annular series of reciprocable rods around said ring element parallel to said shaft, stub shafts rigid with said rods and extending inwardly therefrom and having universal joint connections with said ring element. said ring element being rockable about a transverse axis intersecting its longitudinal axis and being oscillatable in a plane including the axis of said shaft and said transverse axis, and means holding said ring element against rotation about said hub.

2. A structure of the character described comprising a rotatable shaft, a hub fixed with respect to said shaft for rotation therewith, the axis of said hub being inclined relative to the axis of said shaft, a ring element mounted on said hub coaxially therewith and with respect to which said hub is rotatable, an annular series of reciprocable rods around said ring element parallel to said shaft, stub shafts rigid with said rods extending inwardly therefrom and having universal joint connections with said ring element, arms extending from opposite sides of said ring element, said arms being axially alined with each other and with the point of intersection of the axis of said hub with the axis of said shaft, and fixed guide means with which said arms coact to hold said ring element against rotation about said hub, said ring element being rockable about the alined axes of said arms and said arms being mounted in said guide means for oscillatory movement in a plane including the axes of said shaft and said arms.

the universal joint connections between the stub shafts and the ring element comprise spherical rollers disposed in said sockets, and in which the ring element is composed of mating halfsections each having a portion of each socket formed therein.

FREDERICK J. HOLMES. 

